Purple3

• I click a link in an E-Mail. It takes me to the profile of a twitter user, a public page that everybody can see.
  
• I want to "follow" his updates, but I can't find the button.
  
• Ahh, Im not logged in. I log in.
  
• I want to go back to the profile page.
  
• I use back, and see the login page, that makes no longer sense, since I have logged in already.
  
• I use back once more. I get to the profile page. The follow button is missing. I see that the page still doesn't know I have logged in, so I hit refresh (this is the browsers "fault" more or less..)
  
• I see the profile.
  
• I click the "follow" button. I'm finally there.
  

Keep in mind that twitter should be a pretty sophisticated webpage, and I came with a decent browser..